April in Heidelberg averages a daily high of 22.3°C with nights around 11.1°C. Expect roughly 6 wet days totalling 44mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Heidelberg is April–September.
Based on JOHANNESBURG INTERNATIONAL, SF (42.2km), 1995–2024. 20 years of April data.